Schnorr签名中的阈下信道及其封闭方法  

Subliminal Channels and Free Method in Schnorr Signature

作　　者：张应辉[1,2] 马华[1] 王保仓[2] 

机构地区：[1]西安电子科技大学理学院,西安710071 [2]西安电子科技大学计算机网络与信息安全教育部重点实验室,西安710071

出　　处：《电子科技大学学报》2010年第6期826-830,共5页Journal of University of Electronic Science and Technology of China

基　　金：国家自然科学基金(60803149)

摘　　要：分析了阈下信道产生的原因及其在数字签名中的应用,对Schnorr签名中存在的宽带和窄带阈下信道进行了具体分析。设计了一个新的阈下信道封闭协议,新协议要求看守参与会话密钥的生成,确保会话密钥的随机性和隐私性。证明了新协议在保证签名者签名权力的前提下,完全封闭了Schnorr签名中由随机会话密钥所引入的阈下信道。新协议的安全性基于求解离散对数问题的困难性和哈希函数的安全性,在复杂度方面,签名者和看守各执行1次模指数运算。The reasons for the appearance of subliminal channels and their applications in digital signature schemes are analyzed.The wideband and narrowband subliminal channels in the Schnorr signature are discussed.And a new subliminal-free protocol is designed.In the new protocol,the warden participates in the generation of session keys in order to guarantee their randomness and privacy.It is shown that the protocol can completely close the subliminal channels existing in the random session keys in the Schnorr signature scheme.In addition,the signature authority of the signer is guaranteed.The security of the proposed protocol is based on both the discrete logarithm intractability assumption and the existence of collision-free hash functions.To generate a signature,it only needs to perform one modular exponentiation for each of the signer and the warden.

关 键 词：密码学 数字签名 信息隐藏 公钥密码学 数据安全 阈下信道 

分 类 号：TN918[电子电信—通信与信息系统]